There are approximately 33 million individuals with human immunodeficiency virus (HIV) infection worldwide. Many will die as a result of the infection which has already claimed more than 23 million deaths and 2.7 million people are newly infected each year (International AIDS vaccine initiative (IAVI), AIDS vaccine blueprint, A challenge to the field, A road map for progress, 2008, ISBN #0-9792432-8-9). Over 80% of new HIV-1 infections arise in the developing world.
There are approximately 10,000 new cases of hepatitis C virus (HCV) infections in Australia each year, 220,000 HCV-positive individuals in the country (Razali K et al., 2007, Drug Alcohol Depend 91: 228-235), approximately 200 million infected individuals in the world and an estimated 3-4 million new infections each year (Bonner, J. E., Esserman, D., Evon, D. M., 2012, Reliability and validity of a self-efficacy instrument for hepatitis C antiviral treatment regimens, J Viral Hep 19: 316-26). In developing countries, many infections result from poor medical practice (Hauri, A. M, Armstrong, G. L, Hutin Y. J, 2004). The global burden of disease attributable to contaminated injections given in health care settings. Int. J. STD AIDS, 15 (2004), pp. 7-16).
Effective vaccines are necessary to control the spread of these agents. However, existing licensed vaccines often depend on neutralising antibody to induce protection, but neutralising antibody may not effectively control challenge by HCV and HIV. These viruses mutate rapidly and generate neutralising antibody (NAb)-escape mutants. As conventional vaccines elicit NAb, an alternative approach to design vaccines for these viruses is necessary.
There exists a need for alternative vaccines for HIV and HCV. The present invention seeks to overcome, or at least ameliorate, one or more of the deficiencies of the prior art mentioned above, or to provide the consumer with a useful or commercial choice.
The above discussion of the background art is intended to facilitate an understanding of the present invention only. The discussion is not an acknowledgement or admission that any of the material referred to is or was part of the common general knowledge as at the priority date of the application.